The Pentagon (search) on Wednesday gave the go-ahead to begin full-rate production of the V-22 Osprey (search), the hybrid helicopter-airplane that the Marine Corps considers vital to the future of its air fleet.

The Osprey program has been threatened since 23 Marines died in a pair of crashes during testing in 2000.

The go-ahead to start full-scale production was approved by the Defense Acquisition Board (search).

Sen. John Cornyn (search), R-Texas, said before the official announcement that he anticipated that step.

"Full-ation military aircraft, and would be great news for our national security, our troops and the employees at Bell Helicopter," he said.

"As the military transforms to adapt to new and changing threats, this next generation of aircraft will be critical in keeping America safe and ensuring that our troops have the very best."

A joint venture of Boeing Co. (search) and Textron Inc.'s Bell Helicopter (search) unit builds the aircraft in Texas and Pennsylvania.

According to Bell, the current plans include the delivery of 360 aircraft to the Marines, 50 to the U.S. Air Force and 48 to the Navy. The total program is worth in excess of $19 billion to Bell and Textron through 2018.

"With this decision, tilt-rotor technology has come to life in a big way," said Michael A. Redenbaugh, chief executive officer of Bell Helicopter.

A December 2000 Osprey crash in North Carolina, which killed four Marines, was caused by a titanium hydraulic line that ruptured.

A crash earlier that year in Arizona killed 19 Marines and was blamed by investigators on pilot error.

The Osprey tilt-rotor aircraft can land and take off like a helicopter and fly like an airplane. Commanders say the Osprey can haul more troops and equipment farther than existing helicopters. It was designed to replace the aging helicopters in the Marine Corps fleet.